Mixed electrolyte battery

Abstract

A battery (100B) comprises an electrolyte in which a first element forms a redox pair with a second element, wherein the battery (100B) is charged at a voltage sufficient to plate the first element at the anode (122B) and wherein the voltage is insufficient to plate the second element on the anode (122B). Preferred batteries include secondary batteries comprising a mixed electrolyte that includes a redox pair formed by a first element and a second element.

Description

FIELD OF THE INVENTION[0001]The field of the invention is batteries and battery electrolytes.BACKGROUND OF THE INVENTION[0002]Many types of batteries and other power cells are known, based upon a relatively wide range of electrical couples, and among the most popular electrical couples are those containing zinc.[0003]For example, zinc is frequently employed in primary batteries. Such batteries are typically found in many simple flashlight batteries to provide a relatively inexpensive and reliable power source. Although manufacture of Zn / C batteries is typically simple and poses only relatively little environmental impact, various disadvantages of Zn / C batteries exist. Among other things, the ratio of power to weight in commonly used Zn / C batteries is relatively poor.[0004]To improve the power to weight ratio, alternative coupling partners for zinc may be utilized. Among other metal oxides, mercury oxide or silver oxide have been employed to manufacture primary batteries with signifi...

AI Technical Summary

Problems solved by technology

Although manufacture of Zn / C batteries is typically simple and poses only relatively little environmental impact, various disadvantages of Zn / C batteries exist.

Among other things, the ratio of power to weight in commonly used Zn / C batteries is relatively poor.

However, the toxicity of mercury oxide is frequently problematic in manufacture, and tends to become even more problematic when such batteries are discarded.

However, silver oxide is in many instances economically prohibitive, especially where such batteries are used in everyday devices (e.g., portable CD player or radio).

However, reasonable shelf life of such batteries can often only be achieved by using an airtight seal.

Moreover, commercial applications of zinc-air batteries have previously been limited to primary or non-rechargeable types.

Consequently, considerable effort has been made to form a redox pair in which zinc can be used in a secondary, rechargeable battery.

While many rechargeable zinc / nickel batteries frequently exhibit a relatively good power to weight ratio, several problems of the zinc / nickel redox pair persist.

Among other difficulties, such batteries tend to have a comparably poor cycle life of the zinc electrode.

Moreover, nickel is known to be a carcinogen in water-soluble form, and is thus problematic in production and disposal.

Moreover, such batteries typically operate efficiently at extremely high discharge rates and generally have a relatively long dry shelf life.

However, the comparably high cost of the silver electrode generally limits the use of zinc / silver batteries to applications where high energy density is a prime requisite.

However, cadmium is a known toxic element, and thereby further increases the problems associated with health and environmental hazards.

Thus, despite the relatively widespread use of secondary batteries, numerous problems persist.

Loss of the separation (e.g., due to puncture of the membrane by dendrites forming during recharge) will typically result in undesired plating of one or more components of the electrolyte on the battery electrode and thereby dramatically decrease the performance of such batteries.

Although numerous secondary batteries are known in the art, all or almost all of them suffer from one or more disadvantages.

Particularly, the performance of known secondary batteries will significantly decrease when anolyte and catholyte of such batteries will inadvertently mix.

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